GermanApp/Application/DTOs/LessonDto.cs

@@ -10,11 +10,8 @@ public record LessonDto(
     int Id,
     string Title,
     string Description,
-    int LevelId,
+    int Level,
-    string LevelName,
+    string LevelDescription,
-    string LevelCode,
-    int Order,
-    string Topic,
     DateTime CreatedAt,
     DateTime? UpdatedAt);
 
@@ -24,9 +21,7 @@ public record LessonDto(
 public record CreateLessonDto(
     string Title,
     string Description,
-    int LevelId,
+    int Level);
-    int Order,
-    string Topic);
 
 /// <summary>
 /// Data Transfer Object for updating an existing Lesson.
@@ -34,9 +29,7 @@ public record CreateLessonDto(
 public record UpdateLessonDto(
     string Title,
     string Description,
-    int LevelId,
+    int Level);
-    int Order,
-    string Topic);
 
 /// <summary>
 /// Extension methods for mapping between Lesson entity and DTOs.
@@ -47,23 +40,21 @@ public static class LessonDtoExtensions
         lesson.Id,
         lesson.Title,
         lesson.Description,
-        lesson.LevelId,
+        lesson.Level,
-        lesson.Level?.Name ?? "Unknown",
+        GetLevelDescription(lesson.Level),
-        lesson.Level?.Code ?? "??",
-        lesson.Order,
-        lesson.Topic,
         lesson.CreatedAt,
         lesson.UpdatedAt);
 
-    public static Lesson ToEntity(this CreateLessonDto dto) =>
+    private static string GetLevelDescription(int level) => level switch
-        Lesson.Create(dto.LevelId, dto.Title, dto.Order, dto.Topic, dto.Description);
-
-    public static void UpdateFromDto(this Lesson lesson, UpdateLessonDto dto)
     {
-        lesson.UpdateTitle(dto.Title);
+        1 => "A1 (Beginner)",
-        lesson.UpdateDescription(dto.Description);
+        2 => "A2 (Elementary)",
-        lesson.UpdateLevel(dto.LevelId);
+        3 => "B1 (Intermediate)",
-        lesson.UpdateOrder(dto.Order);
+        4 => "B2 (Upper Intermediate)",
-        lesson.UpdateTopic(dto.Topic);
+        5 => "C1 (Advanced)",
-    }
+        _ => "Unknown"
+    };
+
+    public static Lesson ToEntity(this CreateLessonDto dto) =>
+        Lesson.Create(dto.Title, dto.Description, dto.Level);
 }

GermanApp/Application/UseCases/Commands/CreateLessonCommand.cs

@@ -29,7 +29,7 @@ public class CreateLessonCommandHandler : ICommandHandler<CreateLessonCommand, L
         var lesson = command.LessonData.ToEntity();
 
         // Validate business rules (could be extracted to a validator)
-        if (lesson.LevelId < 1 || lesson.LevelId > 5)
+        if (lesson.Level < 1 || lesson.Level > 5)
         {
             throw new ValidationException("Level must be between 1 and 5");
         }

GermanApp/Domain/Entities/Lesson.cs

@@ -1,23 +1,20 @@
 namespace GermanApp.Domain.Entities;
 
 /// <summary>
-/// Represents a lesson in the DeutschLernen system.
+/// Represents a German language lesson in the system.
-/// Lessons are organized within CEFR levels and must be completed in order.
 /// </summary>
 public class Lesson
 {
+    // Private setter for domain behavior, but internal for EF Core
     public int Id { get; private set; }
-    public int LevelId { get; private set; }
     public string Title { get; private set; } = string.Empty;
-    public int Order { get; private set; }
-    public string Topic { get; private set; } = string.Empty;
     public string Description { get; private set; } = string.Empty;
-    public bool IsActive { get; private set; } = true;
+    public int Level { get; private set; }
     public DateTime CreatedAt { get; private set; }
     public DateTime? UpdatedAt { get; private set; }
 
-    // Navigation property (EF Core will handle this)
+    // Navigation properties would go here in EF Core
-    public virtual Level? Level { get; private set; }
+    // public ICollection<VocabularyWord> Words { get; private set; }
 
     /// <summary>
     /// Constructor for EF Core deserialization.
@@ -27,84 +24,35 @@ public class Lesson
     /// <summary>
     /// Factory method to create a new lesson.
     /// </summary>
-    /// <param name="levelId">ID of the parent level</param>
+    public static Lesson Create(string title, string description, int level)
-    /// <param name="title">Title of the lesson</param>
-    /// <param name="order">Sort order within the level</param>
-    /// <param name="topic">Main topic covered in the lesson</param>
-    /// <param name="description">Description of what the lesson covers</param>
-    public static Lesson Create(int levelId, string title, int order, string topic, string description = "")
     {
         return new Lesson
         {
-            LevelId = levelId,
             Title = title,
-            Order = order,
-            Topic = topic,
             Description = description,
+            Level = level,
             CreatedAt = DateTime.UtcNow
         };
     }
 
     /// <summary>
-    /// Updates the lesson's title.
+    /// Updates the lesson details.
     /// </summary>
-    public void UpdateTitle(string newTitle)
+    public void Update(string title, string description, int level)
     {
-        Title = newTitle;
+        Title = title;
+        Description = description;
+        Level = level;
         UpdatedAt = DateTime.UtcNow;
     }
 
     /// <summary>
-    /// Updates the lesson's topic.
+    /// Domain behavior: Check if lesson is at beginner level.
     /// </summary>
-    public void UpdateTopic(string newTopic)
+    public bool IsBeginnerLevel() => Level <= 2;
-    {
-        Topic = newTopic;
-        UpdatedAt = DateTime.UtcNow;
-    }
 
     /// <summary>
-    /// Updates the lesson's description.
+    /// Domain behavior: Check if lesson is at advanced level.
     /// </summary>
-    public void UpdateDescription(string newDescription)
+    public bool IsAdvancedLevel() => Level >= 4;
-    {
-        Description = newDescription;
-        UpdatedAt = DateTime.UtcNow;
-    }
-
-    /// <summary>
-    /// Updates the lesson's sort order.
-    /// </summary>
-    public void UpdateOrder(int newOrder)
-    {
-        Order = newOrder;
-        UpdatedAt = DateTime.UtcNow;
-    }
-
-    /// <summary>
-    /// Updates the lesson's level.
-    /// </summary>
-    public void UpdateLevel(int newLevelId)
-    {
-        LevelId = newLevelId;
-        UpdatedAt = DateTime.UtcNow;
-    }
-
-    /// <summary>
-    /// Activates the lesson.
-    /// </summary>
-    public void Activate()
-    {
-        IsActive = true;
-        UpdatedAt = DateTime.UtcNow;
-    }
-
-    /// <summary>
-    /// Deactivates the lesson.
-    /// </summary>
-    public void Deactivate()
-    {
-        IsActive = false;
-        UpdatedAt = DateTime.UtcNow;
-    }
 }

GermanApp/Domain/Entities/Level.cs

@@ -1,57 +0,0 @@
-namespace GermanApp.Domain.Entities;
-
-/// <summary>
-/// Represents a CEFR level in the DeutschLernen system (A1, A2, B1, B2, C1).
-/// </summary>
-public class Level
-{
-    public int Id { get; private set; }
-    public string Name { get; private set; } = string.Empty;
-    public string Code { get; private set; } = string.Empty;
-    public int Order { get; private set; }
-
-    /// <summary>
-    /// Constructor for EF Core deserialization.
-    /// </summary>
-    private Level() { }
-
-    /// <summary>
-    /// Factory method to create a new level.
-    /// </summary>
-    /// <param name="name">Display name of the level (e.g., "Beginner A1")</param>
-    /// <param name="code">Short code for the level (e.g., "A1")</param>
-    /// <param name="order">Sort order of the level</param>
-    public static Level Create(string name, string code, int order)
-    {
-        return new Level
-        {
-            Name = name,
-            Code = code.ToUpperInvariant(),
-            Order = order
-        };
-    }
-
-    /// <summary>
-    /// Updates the level's display name.
-    /// </summary>
-    public void UpdateName(string newName)
-    {
-        Name = newName;
-    }
-
-    /// <summary>
-    /// Updates the level's code.
-    /// </summary>
-    public void UpdateCode(string newCode)
-    {
-        Code = newCode.ToUpperInvariant();
-    }
-
-    /// <summary>
-    /// Updates the level's sort order.
-    /// </summary>
-    public void UpdateOrder(int newOrder)
-    {
-        Order = newOrder;
-    }
-}

GermanApp/Domain/Entities/UserProgress.cs

@@ -1,82 +0,0 @@
-namespace GermanApp.Domain.Entities;
-
-/// <summary>
-/// Represents a user's progress through lessons.
-/// Tracks completion status and quiz scores.
-/// </summary>
-public class UserProgress
-{
-    public int Id { get; private set; }
-    public int UserId { get; private set; }
-    public int LessonId { get; private set; }
-    public bool IsCompleted { get; private set; }
-    public int QuizScore { get; private set; }
-    public DateTime LastAttemptDate { get; private set; }
-
-    // Navigation properties
-    public virtual User? User { get; private set; }
-    public virtual Lesson? Lesson { get; private set; }
-
-    /// <summary>
-    /// Constructor for EF Core deserialization.
-    /// </summary>
-    private UserProgress() { }
-
-    /// <summary>
-    /// Factory method to create a new user progress record.
-    /// </summary>
-    /// <param name="userId">ID of the user</param>
-    /// <param name="lessonId">ID of the lesson</param>
-    public static UserProgress Create(int userId, int lessonId)
-    {
-        return new UserProgress
-        {
-            UserId = userId,
-            LessonId = lessonId,
-            IsCompleted = false,
-            QuizScore = 0,
-            LastAttemptDate = DateTime.UtcNow
-        };
-    }
-
-    /// <summary>
-    /// Marks the lesson as completed.
-    /// </summary>
-    /// <param name="quizScore">The score achieved on the quiz (0-100)</param>
-    public void MarkAsCompleted(int quizScore)
-    {
-        if (quizScore < 0 || quizScore > 100)
-            throw new ArgumentOutOfRangeException(nameof(quizScore), "Score must be between 0 and 100");
-
-        IsCompleted = true;
-        QuizScore = quizScore;
-        LastAttemptDate = DateTime.UtcNow;
-    }
-
-    /// <summary>
-    /// Updates the quiz score without marking as completed.
-    /// </summary>
-    public void UpdateQuizScore(int quizScore)
-    {
-        if (quizScore < 0 || quizScore > 100)
-            throw new ArgumentOutOfRangeException(nameof(quizScore), "Score must be between 0 and 100");
-
-        QuizScore = quizScore;
-        LastAttemptDate = DateTime.UtcNow;
-    }
-
-    /// <summary>
-    /// Resets the progress (e.g., when user wants to redo a lesson).
-    /// </summary>
-    public void Reset()
-    {
-        IsCompleted = false;
-        QuizScore = 0;
-        LastAttemptDate = DateTime.UtcNow;
-    }
-
-    /// <summary>
-    /// Checks if the user passed the lesson (80% or higher).
-    /// </summary>
-    public bool HasPassed() => QuizScore >= 80;
-}

GermanApp/Domain/Interfaces/IRepository.cs

@@ -41,32 +41,6 @@ public interface IRepository<TEntity, TId> where TEntity : class
     Task<bool> ExistsAsync(TId id, CancellationToken cancellationToken = default);
 }
 
-/// <summary>
-/// Repository interface for Level entities.
-/// </summary>
-public interface ILevelRepository : IRepository<Level, int>
-{
-    /// <summary>
-    /// Gets a level by its code (e.g., "A1", "B2").
-    /// </summary>
-    Task<Level?> GetByCodeAsync(string code, CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets all levels ordered by their sort order.
-    /// </summary>
-    Task<IReadOnlyList<Level>> GetAllOrderedAsync(CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets the first level (lowest order number).
-    /// </summary>
-    Task<Level?> GetFirstLevelAsync(CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets the next level after the specified one.
-    /// </summary>
-    Task<Level?> GetNextLevelAsync(int currentLevelId, CancellationToken cancellationToken = default);
-}
-
 /// <summary>
 /// Repository interface for Lesson entities.
 /// </summary>
@@ -75,61 +49,15 @@ public interface ILessonRepository : IRepository<Lesson, int>
     /// <summary>
     /// Gets lessons by level.
     /// </summary>
-    Task<IReadOnlyList<Lesson>> GetByLevelAsync(int levelId, CancellationToken cancellationToken = default);
+    Task<IReadOnlyList<Lesson>> GetByLevelAsync(int level, CancellationToken cancellationToken = default);
 
     /// <summary>
-    /// Gets all lessons ordered by level and lesson order.
+    /// Gets beginner-level lessons.
     /// </summary>
-    Task<IReadOnlyList<Lesson>> GetAllOrderedAsync(CancellationToken cancellationToken = default);
+    Task<IReadOnlyList<Lesson>> GetBeginnerLessonsAsync(CancellationToken cancellationToken = default);
 
     /// <summary>
-    /// Gets the first lesson in a level.
+    /// Gets advanced-level lessons.
     /// </summary>
-    Task<Lesson?> GetFirstLessonInLevelAsync(int levelId, CancellationToken cancellationToken = default);
+    Task<IReadOnlyList<Lesson>> GetAdvancedLessonsAsync(CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets the next lesson after the specified one (in the same level).
-    /// </summary>
-    Task<Lesson?> GetNextLessonAsync(int currentLessonId, CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets lessons that the user can access (completed previous lessons or first in level).
-    /// </summary>
-    Task<IReadOnlyList<Lesson>> GetAccessibleLessonsAsync(int userId, CancellationToken cancellationToken = default);
-}
-
-/// <summary>
-/// Repository interface for UserProgress entities.
-/// </summary>
-public interface IUserProgressRepository : IRepository<UserProgress, int>
-{
-    /// <summary>
-    /// Gets user progress for a specific user and lesson.
-    /// </summary>
-    Task<UserProgress?> GetByUserAndLessonAsync(int userId, int lessonId, CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets all progress records for a user.
-    /// </summary>
-    Task<IReadOnlyList<UserProgress>> GetByUserAsync(int userId, CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets progress for all lessons in a specific level for a user.
-    /// </summary>
-    Task<IReadOnlyList<UserProgress>> GetByUserAndLevelAsync(int userId, int levelId, CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Checks if a user has completed a lesson (with 80% or higher score).
-    /// </summary>
-    Task<bool> HasUserCompletedLessonAsync(int userId, int lessonId, CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets the user's average score for a level.
-    /// </summary>
-    Task<double> GetAverageScoreForLevelAsync(int userId, int levelId, CancellationToken cancellationToken = default);
-
-    /// <summary>
-    /// Gets the percentage of lessons completed in a level.
-    /// </summary>
-    Task<double> GetLevelCompletionPercentageAsync(int userId, int levelId, CancellationToken cancellationToken = default);
 }

GermanApp/Infrastructure/Data/DbContext/AppDbContext.cs

@@ -14,10 +14,8 @@ public class AppDbContext : Microsoft.EntityFrameworkCore.DbContext
     }
 
     // DbSets for domain entities
-    public DbSet<Level> Levels { get; set; } = null!;
     public DbSet<Lesson> Lessons { get; set; } = null!;
     public DbSet<User> Users { get; set; } = null!;
-    public DbSet<UserProgress> UserProgress { get; set; } = null!;
     public DbSet<RefreshToken> RefreshTokens { get; set; } = null!;
 
     // Note: Value objects are not stored directly as entities.
@@ -27,41 +25,16 @@ public class AppDbContext : Microsoft.EntityFrameworkCore.DbContext
     {
         base.OnModelCreating(modelBuilder);
 
-        // Configure Level entity
-        modelBuilder.Entity<Level>(builder =>
-        {
-            builder.HasKey(l => l.Id);
-            builder.Property(l => l.Name).IsRequired().HasMaxLength(100);
-            builder.Property(l => l.Code).IsRequired().HasMaxLength(10);
-            builder.Property(l => l.Order).IsRequired();
-
-            // Ensure unique constraints
-            builder.HasIndex(l => l.Code).IsUnique();
-            builder.HasIndex(l => l.Order).IsUnique();
-        });
-
         // Configure Lesson entity
         modelBuilder.Entity<Lesson>(builder =>
         {
             builder.HasKey(l => l.Id);
             builder.Property(l => l.Title).IsRequired().HasMaxLength(200);
-            builder.Property(l => l.Description).HasMaxLength(2000);
+            builder.Property(l => l.Description).IsRequired().HasMaxLength(2000);
-            builder.Property(l => l.Topic).IsRequired().HasMaxLength(100);
+            builder.Property(l => l.Level).IsRequired();
-            builder.Property(l => l.LevelId).IsRequired();
-            builder.Property(l => l.Order).IsRequired();
-            builder.Property(l => l.IsActive).HasDefaultValue(true);
             builder.Property(l => l.CreatedAt).IsRequired();
             builder.Property(l => l.UpdatedAt).IsRequired(false);
 
-            // Foreign key to Level with unique constraint per level
-            builder.HasOne(l => l.Level)
-                   .WithMany()
-                   .HasForeignKey(l => l.LevelId)
-                   .OnDelete(DeleteBehavior.Cascade);
-
-            // Unique constraint: one lesson per level per order
-            builder.HasIndex(l => new { l.LevelId, l.Order }).IsUnique();
-
             // Value object: GermanWord would be configured as an owned entity
             // builder.OwnsMany(l => l.Words, wordBuilder =>
             // {
@@ -72,31 +45,6 @@ public class AppDbContext : Microsoft.EntityFrameworkCore.DbContext
             // });
         });
 
-        // Configure UserProgress entity
-        modelBuilder.Entity<UserProgress>(builder =>
-        {
-            builder.HasKey(up => up.Id);
-            builder.Property(up => up.UserId).IsRequired();
-            builder.Property(up => up.LessonId).IsRequired();
-            builder.Property(up => up.IsCompleted).HasDefaultValue(false);
-            builder.Property(up => up.QuizScore).HasDefaultValue(0);
-            builder.Property(up => up.LastAttemptDate).IsRequired();
-
-            // Foreign keys
-            builder.HasOne(up => up.User)
-                   .WithMany()
-                   .HasForeignKey(up => up.UserId)
-                   .OnDelete(DeleteBehavior.Cascade);
-
-            builder.HasOne(up => up.Lesson)
-                   .WithMany()
-                   .HasForeignKey(up => up.LessonId)
-                   .OnDelete(DeleteBehavior.Cascade);
-
-            // Unique constraint: one progress record per user per lesson
-            builder.HasIndex(up => new { up.UserId, up.LessonId }).IsUnique();
-        });
-
         // Configure User entity
         modelBuilder.Entity<User>(builder =>
         {

GermanApp/Infrastructure/Data/Migrations/20260607192743_AddLessonManagementTables.Designer.cs

@@ -1,277 +0,0 @@
-// <auto-generated />
-using System;
-using GermanApp.Infrastructure.Data.DbContext;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.EntityFrameworkCore.Infrastructure;
-using Microsoft.EntityFrameworkCore.Migrations;
-using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
-using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
-
-#nullable disable
-
-namespace GermanApp.Infrastructure.Data.Migrations
-{
-    [DbContext(typeof(AppDbContext))]
-    [Migration("20260607192743_AddLessonManagementTables")]
-    partial class AddLessonManagementTables
-    {
-        /// <inheritdoc />
-        protected override void BuildTargetModel(ModelBuilder modelBuilder)
-        {
-#pragma warning disable 612, 618
-            modelBuilder
-                .HasAnnotation("ProductVersion", "9.0.0")
-                .HasAnnotation("Relational:MaxIdentifierLength", 63);
-
-            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.Lesson", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer");
-
-                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
-
-                    b.Property<DateTime>("CreatedAt")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.Property<string>("Description")
-                        .IsRequired()
-                        .HasMaxLength(2000)
-                        .HasColumnType("character varying(2000)");
-
-                    b.Property<bool>("IsActive")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("boolean")
-                        .HasDefaultValue(true);
-
-                    b.Property<int>("LevelId")
-                        .HasColumnType("integer");
-
-                    b.Property<int>("Order")
-                        .HasColumnType("integer");
-
-                    b.Property<string>("Title")
-                        .IsRequired()
-                        .HasMaxLength(200)
-                        .HasColumnType("character varying(200)");
-
-                    b.Property<string>("Topic")
-                        .IsRequired()
-                        .HasMaxLength(100)
-                        .HasColumnType("character varying(100)");
-
-                    b.Property<DateTime?>("UpdatedAt")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("LevelId", "Order")
-                        .IsUnique();
-
-                    b.ToTable("Lessons");
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.Level", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer");
-
-                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
-
-                    b.Property<string>("Code")
-                        .IsRequired()
-                        .HasMaxLength(10)
-                        .HasColumnType("character varying(10)");
-
-                    b.Property<string>("Name")
-                        .IsRequired()
-                        .HasMaxLength(100)
-                        .HasColumnType("character varying(100)");
-
-                    b.Property<int>("Order")
-                        .HasColumnType("integer");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("Code")
-                        .IsUnique();
-
-                    b.HasIndex("Order")
-                        .IsUnique();
-
-                    b.ToTable("Levels");
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.RefreshToken", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer");
-
-                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
-
-                    b.Property<DateTime>("CreatedAt")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.Property<DateTime>("ExpiresAt")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.Property<bool>("IsActive")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("boolean")
-                        .HasDefaultValue(true);
-
-                    b.Property<DateTime?>("RevokedAt")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.Property<string>("Token")
-                        .IsRequired()
-                        .HasMaxLength(255)
-                        .HasColumnType("character varying(255)");
-
-                    b.Property<int>("UserId")
-                        .HasColumnType("integer");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("UserId");
-
-                    b.ToTable("RefreshTokens");
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.User", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer");
-
-                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
-
-                    b.Property<DateTime>("CreatedAt")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.Property<string>("CurrentLevel")
-                        .IsRequired()
-                        .ValueGeneratedOnAdd()
-                        .HasMaxLength(10)
-                        .HasColumnType("character varying(10)")
-                        .HasDefaultValue("A1");
-
-                    b.Property<string>("Email")
-                        .IsRequired()
-                        .HasMaxLength(100)
-                        .HasColumnType("character varying(100)");
-
-                    b.Property<string>("PasswordHash")
-                        .IsRequired()
-                        .HasMaxLength(255)
-                        .HasColumnType("character varying(255)");
-
-                    b.Property<int>("Streak")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer")
-                        .HasDefaultValue(0);
-
-                    b.Property<int>("TotalPoints")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer")
-                        .HasDefaultValue(0);
-
-                    b.Property<string>("Username")
-                        .IsRequired()
-                        .HasMaxLength(50)
-                        .HasColumnType("character varying(50)");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("Email")
-                        .IsUnique();
-
-                    b.HasIndex("Username")
-                        .IsUnique();
-
-                    b.ToTable("Users");
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.UserProgress", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer");
-
-                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
-
-                    b.Property<bool>("IsCompleted")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("boolean")
-                        .HasDefaultValue(false);
-
-                    b.Property<DateTime>("LastAttemptDate")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.Property<int>("LessonId")
-                        .HasColumnType("integer");
-
-                    b.Property<int>("QuizScore")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer")
-                        .HasDefaultValue(0);
-
-                    b.Property<int>("UserId")
-                        .HasColumnType("integer");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("LessonId");
-
-                    b.HasIndex("UserId", "LessonId")
-                        .IsUnique();
-
-                    b.ToTable("UserProgress");
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.Lesson", b =>
-                {
-                    b.HasOne("GermanApp.Domain.Entities.Level", "Level")
-                        .WithMany()
-                        .HasForeignKey("LevelId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-
-                    b.Navigation("Level");
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.RefreshToken", b =>
-                {
-                    b.HasOne("GermanApp.Domain.Entities.User", null)
-                        .WithMany()
-                        .HasForeignKey("UserId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.UserProgress", b =>
-                {
-                    b.HasOne("GermanApp.Domain.Entities.Lesson", "Lesson")
-                        .WithMany()
-                        .HasForeignKey("LessonId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-
-                    b.HasOne("GermanApp.Domain.Entities.User", "User")
-                        .WithMany()
-                        .HasForeignKey("UserId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-
-                    b.Navigation("Lesson");
-
-                    b.Navigation("User");
-                });
-#pragma warning restore 612, 618
-        }
-    }
-}

GermanApp/Infrastructure/Data/Migrations/20260607192743_AddLessonManagementTables.cs

@@ -1,159 +0,0 @@
-using System;
-using Microsoft.EntityFrameworkCore.Migrations;
-using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
-
-#nullable disable
-
-namespace GermanApp.Infrastructure.Data.Migrations
-{
-    /// <inheritdoc />
-    public partial class AddLessonManagementTables : Migration
-    {
-        /// <inheritdoc />
-        protected override void Up(MigrationBuilder migrationBuilder)
-        {
-            migrationBuilder.RenameColumn(
-                name: "Level",
-                table: "Lessons",
-                newName: "Order");
-
-            migrationBuilder.AddColumn<bool>(
-                name: "IsActive",
-                table: "Lessons",
-                type: "boolean",
-                nullable: false,
-                defaultValue: true);
-
-            migrationBuilder.AddColumn<int>(
-                name: "LevelId",
-                table: "Lessons",
-                type: "integer",
-                nullable: false,
-                defaultValue: 0);
-
-            migrationBuilder.AddColumn<string>(
-                name: "Topic",
-                table: "Lessons",
-                type: "character varying(100)",
-                maxLength: 100,
-                nullable: false,
-                defaultValue: "");
-
-            migrationBuilder.CreateTable(
-                name: "Levels",
-                columns: table => new
-                {
-                    Id = table.Column<int>(type: "integer", nullable: false)
-                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
-                    Name = table.Column<string>(type: "character varying(100)", maxLength: 100, nullable: false),
-                    Code = table.Column<string>(type: "character varying(10)", maxLength: 10, nullable: false),
-                    Order = table.Column<int>(type: "integer", nullable: false)
-                },
-                constraints: table =>
-                {
-                    table.PrimaryKey("PK_Levels", x => x.Id);
-                });
-
-            migrationBuilder.CreateTable(
-                name: "UserProgress",
-                columns: table => new
-                {
-                    Id = table.Column<int>(type: "integer", nullable: false)
-                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
-                    UserId = table.Column<int>(type: "integer", nullable: false),
-                    LessonId = table.Column<int>(type: "integer", nullable: false),
-                    IsCompleted = table.Column<bool>(type: "boolean", nullable: false, defaultValue: false),
-                    QuizScore = table.Column<int>(type: "integer", nullable: false, defaultValue: 0),
-                    LastAttemptDate = table.Column<DateTime>(type: "timestamp with time zone", nullable: false)
-                },
-                constraints: table =>
-                {
-                    table.PrimaryKey("PK_UserProgress", x => x.Id);
-                    table.ForeignKey(
-                        name: "FK_UserProgress_Lessons_LessonId",
-                        column: x => x.LessonId,
-                        principalTable: "Lessons",
-                        principalColumn: "Id",
-                        onDelete: ReferentialAction.Cascade);
-                    table.ForeignKey(
-                        name: "FK_UserProgress_Users_UserId",
-                        column: x => x.UserId,
-                        principalTable: "Users",
-                        principalColumn: "Id",
-                        onDelete: ReferentialAction.Cascade);
-                });
-
-            migrationBuilder.CreateIndex(
-                name: "IX_Lessons_LevelId_Order",
-                table: "Lessons",
-                columns: new[] { "LevelId", "Order" },
-                unique: true);
-
-            migrationBuilder.CreateIndex(
-                name: "IX_Levels_Code",
-                table: "Levels",
-                column: "Code",
-                unique: true);
-
-            migrationBuilder.CreateIndex(
-                name: "IX_Levels_Order",
-                table: "Levels",
-                column: "Order",
-                unique: true);
-
-            migrationBuilder.CreateIndex(
-                name: "IX_UserProgress_LessonId",
-                table: "UserProgress",
-                column: "LessonId");
-
-            migrationBuilder.CreateIndex(
-                name: "IX_UserProgress_UserId_LessonId",
-                table: "UserProgress",
-                columns: new[] { "UserId", "LessonId" },
-                unique: true);
-
-            migrationBuilder.AddForeignKey(
-                name: "FK_Lessons_Levels_LevelId",
-                table: "Lessons",
-                column: "LevelId",
-                principalTable: "Levels",
-                principalColumn: "Id",
-                onDelete: ReferentialAction.Cascade);
-        }
-
-        /// <inheritdoc />
-        protected override void Down(MigrationBuilder migrationBuilder)
-        {
-            migrationBuilder.DropForeignKey(
-                name: "FK_Lessons_Levels_LevelId",
-                table: "Lessons");
-
-            migrationBuilder.DropTable(
-                name: "Levels");
-
-            migrationBuilder.DropTable(
-                name: "UserProgress");
-
-            migrationBuilder.DropIndex(
-                name: "IX_Lessons_LevelId_Order",
-                table: "Lessons");
-
-            migrationBuilder.DropColumn(
-                name: "IsActive",
-                table: "Lessons");
-
-            migrationBuilder.DropColumn(
-                name: "LevelId",
-                table: "Lessons");
-
-            migrationBuilder.DropColumn(
-                name: "Topic",
-                table: "Lessons");
-
-            migrationBuilder.RenameColumn(
-                name: "Order",
-                table: "Lessons",
-                newName: "Level");
-        }
-    }
-}

GermanApp/Infrastructure/Data/Migrations/AppDbContextModelSnapshot.cs

@@ -38,15 +38,7 @@ namespace GermanApp.Migrations
                         .HasMaxLength(2000)
                         .HasColumnType("character varying(2000)");
 
-                    b.Property<bool>("IsActive")
+                    b.Property<int>("Level")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("boolean")
-                        .HasDefaultValue(true);
-
-                    b.Property<int>("LevelId")
-                        .HasColumnType("integer");
-
-                    b.Property<int>("Order")
                         .HasColumnType("integer");
 
                     b.Property<string>("Title")
@@ -54,54 +46,14 @@ namespace GermanApp.Migrations
                         .HasMaxLength(200)
                         .HasColumnType("character varying(200)");
 
-                    b.Property<string>("Topic")
-                        .IsRequired()
-                        .HasMaxLength(100)
-                        .HasColumnType("character varying(100)");
-
                     b.Property<DateTime?>("UpdatedAt")
                         .HasColumnType("timestamp with time zone");
 
                     b.HasKey("Id");
 
-                    b.HasIndex("LevelId", "Order")
-                        .IsUnique();
-
                     b.ToTable("Lessons");
                 });
 
-            modelBuilder.Entity("GermanApp.Domain.Entities.Level", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer");
-
-                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
-
-                    b.Property<string>("Code")
-                        .IsRequired()
-                        .HasMaxLength(10)
-                        .HasColumnType("character varying(10)");
-
-                    b.Property<string>("Name")
-                        .IsRequired()
-                        .HasMaxLength(100)
-                        .HasColumnType("character varying(100)");
-
-                    b.Property<int>("Order")
-                        .HasColumnType("integer");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("Code")
-                        .IsUnique();
-
-                    b.HasIndex("Order")
-                        .IsUnique();
-
-                    b.ToTable("Levels");
-                });
-
             modelBuilder.Entity("GermanApp.Domain.Entities.RefreshToken", b =>
                 {
                     b.Property<int>("Id")
@@ -193,54 +145,6 @@ namespace GermanApp.Migrations
                     b.ToTable("Users");
                 });
 
-            modelBuilder.Entity("GermanApp.Domain.Entities.UserProgress", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer");
-
-                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
-
-                    b.Property<bool>("IsCompleted")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("boolean")
-                        .HasDefaultValue(false);
-
-                    b.Property<DateTime>("LastAttemptDate")
-                        .HasColumnType("timestamp with time zone");
-
-                    b.Property<int>("LessonId")
-                        .HasColumnType("integer");
-
-                    b.Property<int>("QuizScore")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("integer")
-                        .HasDefaultValue(0);
-
-                    b.Property<int>("UserId")
-                        .HasColumnType("integer");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("LessonId");
-
-                    b.HasIndex("UserId", "LessonId")
-                        .IsUnique();
-
-                    b.ToTable("UserProgress");
-                });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.Lesson", b =>
-                {
-                    b.HasOne("GermanApp.Domain.Entities.Level", "Level")
-                        .WithMany()
-                        .HasForeignKey("LevelId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-
-                    b.Navigation("Level");
-                });
-
             modelBuilder.Entity("GermanApp.Domain.Entities.RefreshToken", b =>
                 {
                     b.HasOne("GermanApp.Domain.Entities.User", null)
@@ -249,25 +153,6 @@ namespace GermanApp.Migrations
                         .OnDelete(DeleteBehavior.Cascade)
                         .IsRequired();
                 });
-
-            modelBuilder.Entity("GermanApp.Domain.Entities.UserProgress", b =>
-                {
-                    b.HasOne("GermanApp.Domain.Entities.Lesson", "Lesson")
-                        .WithMany()
-                        .HasForeignKey("LessonId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-
-                    b.HasOne("GermanApp.Domain.Entities.User", "User")
-                        .WithMany()
-                        .HasForeignKey("UserId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-
-                    b.Navigation("Lesson");
-
-                    b.Navigation("User");
-                });
 #pragma warning restore 612, 618
         }
     }

GermanApp/Infrastructure/Data/Repositories/LessonRepository.cs

@@ -21,14 +21,12 @@ public class LessonRepository : ILessonRepository
     public async Task<Lesson?> GetByIdAsync(int id, CancellationToken cancellationToken = default)
     {
         return await _context.Lessons
-            .Include(l => l.Level)
             .FirstOrDefaultAsync(l => l.Id == id, cancellationToken);
     }
 
     public async Task<IReadOnlyList<Lesson>> GetAllAsync(CancellationToken cancellationToken = default)
     {
         return await _context.Lessons
-            .Include(l => l.Level)
             .AsNoTracking()
             .ToListAsync(cancellationToken);
     }
@@ -58,104 +56,27 @@ public class LessonRepository : ILessonRepository
             .AnyAsync(l => l.Id == id, cancellationToken);
     }
 
-    public async Task<IReadOnlyList<Lesson>> GetByLevelAsync(int levelId, CancellationToken cancellationToken = default)
+    public async Task<IReadOnlyList<Lesson>> GetByLevelAsync(int level, CancellationToken cancellationToken = default)
     {
         return await _context.Lessons
-            .Include(l => l.Level)
+            .Where(l => l.Level == level)
-            .Where(l => l.LevelId == levelId)
-            .OrderBy(l => l.Order)
             .AsNoTracking()
             .ToListAsync(cancellationToken);
     }
 
-    public async Task<IReadOnlyList<Lesson>> GetAllOrderedAsync(CancellationToken cancellationToken = default)
+    public async Task<IReadOnlyList<Lesson>> GetBeginnerLessonsAsync(CancellationToken cancellationToken = default)
     {
         return await _context.Lessons
-            .Include(l => l.Level)
+            .Where(l => l.Level <= 2)
-            .OrderBy(l => l.Level.Order)
-            .ThenBy(l => l.Order)
             .AsNoTracking()
             .ToListAsync(cancellationToken);
     }
 
-    public async Task<Lesson?> GetFirstLessonInLevelAsync(int levelId, CancellationToken cancellationToken = default)
+    public async Task<IReadOnlyList<Lesson>> GetAdvancedLessonsAsync(CancellationToken cancellationToken = default)
     {
         return await _context.Lessons
-            .Include(l => l.Level)
+            .Where(l => l.Level >= 4)
-            .Where(l => l.LevelId == levelId)
-            .OrderBy(l => l.Order)
-            .FirstOrDefaultAsync(cancellationToken);
-    }
-
-    public async Task<Lesson?> GetNextLessonAsync(int currentLessonId, CancellationToken cancellationToken = default)
-    {
-        var currentLesson = await _context.Lessons
-            .Where(l => l.Id == currentLessonId)
-            .Select(l => new { l.LevelId, l.Order })
-            .FirstOrDefaultAsync(cancellationToken);
-
-        if (currentLesson == null)
-            return null;
-
-        return await _context.Lessons
-            .Include(l => l.Level)
-            .Where(l => l.LevelId == currentLesson.LevelId && l.Order > currentLesson.Order)
-            .OrderBy(l => l.Order)
-            .FirstOrDefaultAsync(cancellationToken);
-    }
-
-    public async Task<IReadOnlyList<Lesson>> GetAccessibleLessonsAsync(int userId, CancellationToken cancellationToken = default)
-    {
-        // Get all lessons ordered by level and lesson order
-        var allLessons = await _context.Lessons
-            .Include(l => l.Level)
-            .OrderBy(l => l.Level.Order)
-            .ThenBy(l => l.Order)
             .AsNoTracking()
             .ToListAsync(cancellationToken);
-
-        if (allLessons.Count == 0)
-            return new List<Lesson>();
-
-        // Get completed lessons for this user
-        var completedLessonIds = await _context.UserProgress
-            .Where(up => up.UserId == userId && up.IsCompleted)
-            .Select(up => up.LessonId)
-            .ToListAsync(cancellationToken);
-
-        // Find the first lesson in the first level
-        var firstLesson = allLessons.First();
-        
-        // If user hasn't completed any lessons, they can only access the first one
-        if (completedLessonIds.Count == 0)
-            return new List<Lesson> { firstLesson };
-
-        // Get the highest ordered lesson that the user has completed
-        var completedLessons = allLessons
-            .Where(l => completedLessonIds.Contains(l.Id))
-            .OrderBy(l => l.Level.Order)
-            .ThenBy(l => l.Order)
-            .ToList();
-
-        if (completedLessons.Count == 0)
-            return new List<Lesson> { firstLesson };
-
-        var lastCompleted = completedLessons.Last();
-        
-        // User can access all lessons up to and including the next one after the last completed
-        var accessibleLessons = allLessons
-            .TakeWhile(l => l.Id != lastCompleted.Id)
-            .ToList();
-        
-        // Add the last completed and the next one
-        accessibleLessons.Add(lastCompleted);
-        
-        var nextLessonIndex = allLessons.FindIndex(l => l.Id == lastCompleted.Id) + 1;
-        if (nextLessonIndex < allLessons.Count)
-        {
-            accessibleLessons.Add(allLessons[nextLessonIndex]);
-        }
-
-        return accessibleLessons;
     }
 }

GermanApp/Infrastructure/Data/Repositories/LevelRepository.cs

@@ -1,95 +0,0 @@
-using GermanApp.Domain.Entities;
-using GermanApp.Domain.Interfaces;
-using GermanApp.Infrastructure.Data.DbContext;
-using Microsoft.EntityFrameworkCore;
-
-namespace GermanApp.Infrastructure.Data.Repositories;
-
-/// <summary>
-/// Entity Framework Core implementation of ILevelRepository.
-/// This is part of the Infrastructure layer.
-/// </summary>
-public class LevelRepository : ILevelRepository
-{
-    private readonly AppDbContext _context;
-
-    public LevelRepository(AppDbContext context)
-    {
-        _context = context;
-    }
-
-    public async Task<Level?> GetByIdAsync(int id, CancellationToken cancellationToken = default)
-    {
-        return await _context.Levels
-            .FirstOrDefaultAsync(l => l.Id == id, cancellationToken);
-    }
-
-    public async Task<IReadOnlyList<Level>> GetAllAsync(CancellationToken cancellationToken = default)
-    {
-        return await _context.Levels
-            .AsNoTracking()
-            .ToListAsync(cancellationToken);
-    }
-
-    public async Task<Level> AddAsync(Level entity, CancellationToken cancellationToken = default)
-    {
-        await _context.Levels.AddAsync(entity, cancellationToken);
-        await _context.SaveChangesAsync(cancellationToken);
-        return entity;
-    }
-
-    public async Task UpdateAsync(Level entity, CancellationToken cancellationToken = default)
-    {
-        _context.Levels.Update(entity);
-        await _context.SaveChangesAsync(cancellationToken);
-    }
-
-    public async Task DeleteAsync(Level entity, CancellationToken cancellationToken = default)
-    {
-        _context.Levels.Remove(entity);
-        await _context.SaveChangesAsync(cancellationToken);
-    }
-
-    public async Task<bool> ExistsAsync(int id, CancellationToken cancellationToken = default)
-    {
-        return await _context.Levels
-            .AnyAsync(l => l.Id == id, cancellationToken);
-    }
-
-    public async Task<Level?> GetByCodeAsync(string code, CancellationToken cancellationToken = default)
-    {
-        return await _context.Levels
-            .FirstOrDefaultAsync(l => l.Code == code.ToUpperInvariant(), cancellationToken);
-    }
-
-    public async Task<IReadOnlyList<Level>> GetAllOrderedAsync(CancellationToken cancellationToken = default)
-    {
-        return await _context.Levels
-            .OrderBy(l => l.Order)
-            .AsNoTracking()
-            .ToListAsync(cancellationToken);
-    }
-
-    public async Task<Level?> GetFirstLevelAsync(CancellationToken cancellationToken = default)
-    {
-        return await _context.Levels
-            .OrderBy(l => l.Order)
-            .FirstOrDefaultAsync(cancellationToken);
-    }
-
-    public async Task<Level?> GetNextLevelAsync(int currentLevelId, CancellationToken cancellationToken = default)
-    {
-        var currentLevel = await _context.Levels
-            .Where(l => l.Id == currentLevelId)
-            .Select(l => l.Order)
-            .FirstOrDefaultAsync(cancellationToken);
-
-        if (currentLevel == default)
-            return null;
-
-        return await _context.Levels
-            .Where(l => l.Order > currentLevel)
-            .OrderBy(l => l.Order)
-            .FirstOrDefaultAsync(cancellationToken);
-    }
-}

GermanApp/Infrastructure/Data/Repositories/UserProgressRepository.cs

@@ -1,127 +0,0 @@
-using GermanApp.Domain.Entities;
-using GermanApp.Domain.Interfaces;
-using GermanApp.Infrastructure.Data.DbContext;
-using Microsoft.EntityFrameworkCore;
-
-namespace GermanApp.Infrastructure.Data.Repositories;
-
-/// <summary>
-/// Entity Framework Core implementation of IUserProgressRepository.
-/// This is part of the Infrastructure layer.
-/// </summary>
-public class UserProgressRepository : IUserProgressRepository
-{
-    private readonly AppDbContext _context;
-
-    public UserProgressRepository(AppDbContext context)
-    {
-        _context = context;
-    }
-
-    public async Task<UserProgress?> GetByIdAsync(int id, CancellationToken cancellationToken = default)
-    {
-        return await _context.UserProgress
-            .Include(up => up.User)
-            .Include(up => up.Lesson)
-            .FirstOrDefaultAsync(up => up.Id == id, cancellationToken);
-    }
-
-    public async Task<IReadOnlyList<UserProgress>> GetAllAsync(CancellationToken cancellationToken = default)
-    {
-        return await _context.UserProgress
-            .Include(up => up.User)
-            .Include(up => up.Lesson)
-            .AsNoTracking()
-            .ToListAsync(cancellationToken);
-    }
-
-    public async Task<UserProgress> AddAsync(UserProgress entity, CancellationToken cancellationToken = default)
-    {
-        await _context.UserProgress.AddAsync(entity, cancellationToken);
-        await _context.SaveChangesAsync(cancellationToken);
-        return entity;
-    }
-
-    public async Task UpdateAsync(UserProgress entity, CancellationToken cancellationToken = default)
-    {
-        _context.UserProgress.Update(entity);
-        await _context.SaveChangesAsync(cancellationToken);
-    }
-
-    public async Task DeleteAsync(UserProgress entity, CancellationToken cancellationToken = default)
-    {
-        _context.UserProgress.Remove(entity);
-        await _context.SaveChangesAsync(cancellationToken);
-    }
-
-    public async Task<bool> ExistsAsync(int id, CancellationToken cancellationToken = default)
-    {
-        return await _context.UserProgress
-            .AnyAsync(up => up.Id == id, cancellationToken);
-    }
-
-    public async Task<UserProgress?> GetByUserAndLessonAsync(int userId, int lessonId, CancellationToken cancellationToken = default)
-    {
-        return await _context.UserProgress
-            .Include(up => up.User)
-            .Include(up => up.Lesson)
-            .FirstOrDefaultAsync(up => up.UserId == userId && up.LessonId == lessonId, cancellationToken);
-    }
-
-    public async Task<IReadOnlyList<UserProgress>> GetByUserAsync(int userId, CancellationToken cancellationToken = default)
-    {
-        return await _context.UserProgress
-            .Include(up => up.Lesson)
-            .ThenInclude(l => l.Level)
-            .Where(up => up.UserId == userId)
-            .OrderBy(up => up.Lesson.Level!.Order)
-            .ThenBy(up => up.Lesson.Order)
-            .AsNoTracking()
-            .ToListAsync(cancellationToken);
-    }
-
-    public async Task<IReadOnlyList<UserProgress>> GetByUserAndLevelAsync(int userId, int levelId, CancellationToken cancellationToken = default)
-    {
-        return await _context.UserProgress
-            .Include(up => up.Lesson)
-            .Where(up => up.UserId == userId && up.Lesson.LevelId == levelId)
-            .OrderBy(up => up.Lesson.Order)
-            .AsNoTracking()
-            .ToListAsync(cancellationToken);
-    }
-
-    public async Task<bool> HasUserCompletedLessonAsync(int userId, int lessonId, CancellationToken cancellationToken = default)
-    {
-        return await _context.UserProgress
-            .AnyAsync(up => up.UserId == userId && up.LessonId == lessonId && up.IsCompleted, cancellationToken);
-    }
-
-    public async Task<double> GetAverageScoreForLevelAsync(int userId, int levelId, CancellationToken cancellationToken = default)
-    {
-        var progresses = await _context.UserProgress
-            .Where(up => up.UserId == userId && up.Lesson.LevelId == levelId && up.QuizScore > 0)
-            .Select(up => up.QuizScore)
-            .ToListAsync(cancellationToken);
-
-        if (progresses.Count == 0)
-            return 0;
-
-        return progresses.Average();
-    }
-
-    public async Task<double> GetLevelCompletionPercentageAsync(int userId, int levelId, CancellationToken cancellationToken = default)
-    {
-        // Get total lessons in the level
-        var totalLessons = await _context.Lessons
-            .CountAsync(l => l.LevelId == levelId, cancellationToken);
-
-        if (totalLessons == 0)
-            return 0;
-
-        // Get completed lessons count for user in this level
-        var completedCount = await _context.UserProgress
-            .CountAsync(up => up.UserId == userId && up.Lesson.LevelId == levelId && up.IsCompleted, cancellationToken);
-
-        return (double)completedCount / totalLessons * 100;
-    }
-}

GermanApp/Infrastructure/Data/SeedData/SeedDataExtension.cs

@@ -13,7 +13,7 @@ public static class SeedDataExtension
     /// Seeds the database with initial data.
     /// </summary>
     /// <param name="app">The web application</param>
-    public static async Task SeedDatabaseAsync(this WebApplication app)
+    public static void SeedDatabase(this WebApplication app)
     {
         using var scope = app.Services.CreateScope();
         var dbContext = scope.ServiceProvider.GetRequiredService<AppDbContext>();
@@ -24,18 +24,6 @@ public static class SeedDataExtension
         // Only seed if there are no users
         if (!dbContext.Users.Any())
         {
-            // Seed CEFR levels first
-            var levels = new[]
-            {
-                Level.Create("Beginner A1", "A1", 1),
-                Level.Create("Elementary A2", "A2", 2),
-                Level.Create("Intermediate B1", "B1", 3),
-                Level.Create("Upper Intermediate B2", "B2", 4),
-                Level.Create("Advanced C1", "C1", 5)
-            };
-            dbContext.Levels.AddRange(levels);
-            await dbContext.SaveChangesAsync();
-
             // Seed an admin user
             var adminUser = User.Create(
                 "admin",
@@ -56,17 +44,17 @@ public static class SeedDataExtension
             // Seed some lessons
             var lessons = new[]
             {
-                Lesson.Create(1, "Greetings", 1, "Greetings", "Basic German greetings and introductions"),
+                Lesson.Create("Greetings", "Basic German greetings and introductions", 1),
-                Lesson.Create(1, "Numbers", 2, "Numbers", "German numbers 1-100"),
+                Lesson.Create("Numbers", "German numbers 1-100", 1),
-                Lesson.Create(2, "Grammar Basics", 1, "Grammar", "Basic German grammar rules"),
+                Lesson.Create("Grammar Basics", "Basic German grammar rules", 2),
-                Lesson.Create(2, "Everyday Phrases", 2, "Phrases", "Common phrases for daily conversations"),
+                Lesson.Create("Everyday Phrases", "Common phrases for daily conversations", 2),
-                Lesson.Create(5, "Advanced Grammar", 1, "Grammar", "Complex German grammar")
+                Lesson.Create("Advanced Grammar", "Complex German grammar", 4)
             };
             dbContext.Lessons.AddRange(lessons);
 
-            await dbContext.SaveChangesAsync();
+            dbContext.SaveChanges();
 
-            Console.WriteLine("Database seeded with levels, admin user, test user, and sample lessons.");
+            Console.WriteLine("Database seeded with admin user, test user, and sample lessons.");
         }
     }
 }

GermanApp/Presentation/Endpoints/LessonsEndpoints.cs

@@ -1,6 +1,5 @@
 using GermanApp.Application.DTOs;
 using GermanApp.Application.UseCases.Commands;
-using GermanApp.Domain.Entities;
 using GermanApp.Domain.Interfaces;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -46,13 +45,8 @@ public static class LessonsEndpoints
         // GET /api/lessons/beginner
         group.MapGet("/beginner", async ([FromServices] ILessonRepository repository) =>
         {
-            // Beginner lessons are A1 (level 1) and A2 (level 2)
+            var lessons = await repository.GetBeginnerLessonsAsync();
-            var beginnerLessons = new List<Lesson>();
+            return Results.Ok(lessons.Select(l => l.ToDto()));
-            var level1Lessons = await repository.GetByLevelAsync(1);
-            var level2Lessons = await repository.GetByLevelAsync(2);
-            beginnerLessons.AddRange(level1Lessons);
-            beginnerLessons.AddRange(level2Lessons);
-            return Results.Ok(beginnerLessons.OrderBy(l => l.LevelId).ThenBy(l => l.Order).Select(l => l.ToDto()));
         })
         .WithName("GetBeginnerLessons")
         .WithOpenApi(operation => new(operation)
@@ -64,13 +58,8 @@ public static class LessonsEndpoints
         // GET /api/lessons/advanced
         group.MapGet("/advanced", async ([FromServices] ILessonRepository repository) =>
         {
-            // Advanced lessons are B2 (level 4) and C1 (level 5)
+            var lessons = await repository.GetAdvancedLessonsAsync();
-            var advancedLessons = new List<Lesson>();
+            return Results.Ok(lessons.Select(l => l.ToDto()));
-            var level4Lessons = await repository.GetByLevelAsync(4);
-            var level5Lessons = await repository.GetByLevelAsync(5);
-            advancedLessons.AddRange(level4Lessons);
-            advancedLessons.AddRange(level5Lessons);
-            return Results.Ok(advancedLessons.OrderBy(l => l.LevelId).ThenBy(l => l.Order).Select(l => l.ToDto()));
         })
         .WithName("GetAdvancedLessons")
         .WithOpenApi(operation => new(operation)
@@ -121,7 +110,7 @@ public static class LessonsEndpoints
                 return Results.NotFound();
 
             // Map DTO to entity
-            existingLesson.UpdateFromDto(dto);
+            existingLesson.Update(dto.Title, dto.Description, dto.Level);
             await repository.UpdateAsync(existingLesson);
 
             return Results.Ok(existingLesson.ToDto());

GermanApp/Program.cs

@@ -153,15 +153,12 @@ try
         name: "api",
         pattern: "api/{controller}/{action}/{id?}" );
 
+    // Seed database with initial data
+    app.SeedDatabase();
+
     // Map Clean Architecture endpoints
     app.MapLessonsEndpoints();
 
-    // Seed database with initial data
-    if (app.Environment.IsDevelopment())
-    {
-        await app.SeedDatabaseAsync();
-    }
-
     // Keep original WeatherForecast endpoint for reference
     app.MapGet("/weatherforecast", () =>
     {

docs/ROADMAP.md

@@ -91,7 +91,7 @@ Implement the core backend functionality, including lesson management, AI servic
 ### Features
 | # | Feature | Description | Hours | Status | Dependencies |
 |---|---------|-------------|-------|--------|--------------|
-| 2.1 | [Lesson Management](features/lesson-management.md) | Lessons, levels, progress tracking | 10-16h | 🚀 In Progress (Phase 1: DB & Models ✅) | Phase 1 |
+| 2.1 | [Lesson Management](features/lesson-management.md) | Lessons, levels, progress tracking | 10-16h | ⏳ Planned | Phase 1 |
 | 2.2 | [AI Services](features/ai-services.md) | Mistral, Vosk, Coqui TTS integration | 10-16h | ⏳ Planned | Phase 1 |
 | 2.3 | [Vocabulary System](features/vocabulary-system.md) | Word storage, audio, import | 8-12h | ⏳ Planned | Phase 1, 2.1 |
 | 2.4 | [Quiz System](features/quiz-system.md) | Multiple question types, scoring | 6-10h | ⏳ Planned | Phase 1, 2.1 |
@@ -265,8 +265,8 @@ Implement the complete React + TypeScript frontend application with all UI compo
 
 | Phase | Duration | Hours | Features | Status |
 |-------|----------|-------|----------|--------|
-| Phase 1: Foundation | 2 weeks | 30-42h | 2 | ✅ Complete (1.1 ✅, 1.2 ✅) |
+| Phase 1: Foundation | 2 weeks | 30-42h | 2 | 🚀 In Progress (1.1 ✅, 1.2 🚀) |
-| Phase 2: Core Backend | 2 weeks | 42-58h | 4 | 🚀 In Progress (2.1 🚀) |
+| Phase 2: Core Backend | 2 weeks | 42-58h | 4 | ⏳ Planned |
 | Phase 3: Content & Features | 2 weeks | 30-42h | 2 | ⏳ Planned |
 | Phase 4: Frontend | 2 weeks | 10-16h | 1 | ⏳ Planned |
 | **Total** | **8 weeks** | **112-158h** | **9** | 🚀 In Progress |

docs/features/lesson-management.md

@@ -1,6 +1,6 @@
 # Feature: Lesson & Content Management
 
-> **Status**: 🚀 In Progress  
+> **Status**: ⏳ Planned  
 > **Priority**: High  
 > **Complexity**: High  
 > **Estimate**: 10-16 hours  
@@ -10,8 +10,6 @@
 > **PR**: -  
 > **Related Features**: Infrastructure Setup, User Authentication, Vocabulary System, Quiz System, Story Integration
 
-**Phase 1: Database & Models - COMPLETED ✅**
-
 ---
 
 ## 📌 Overview
@@ -134,12 +132,12 @@ Each lesson contains:
 ## 🚀 Implementation Plan
 
 ### Phase 1: Database & Models (2-3 hours)
-- [x] Create Level entity and repository
+- [ ] Create Level entity and repository
-- [x] Create Lesson entity and repository
+- [ ] Create Lesson entity and repository
-- [x] Create UserProgress entity and repository
+- [ ] Create UserProgress entity and repository
-- [x] Set up relationships between entities
+- [ ] Set up relationships between entities
-- [x] Create migrations for Levels, Lessons, UserProgress
+- [ ] Create migrations for Levels, Lessons, UserProgress
-- [x] Seed initial A1 level and lessons
+- [ ] Seed initial A1 level and lessons
 
 ### Phase 2: Backend Services (3-5 hours)
 - [ ] Create LevelService with CRUD operations
@@ -182,16 +180,16 @@ Each lesson contains:
 ## ✅ Tasks
 
 ### Backend
-- [x] Create Domain/Entities/Level.cs
+- [ ] Create Domain/Entities/Level.cs
-- [x] Create Domain/Entities/Lesson.cs
+- [ ] Create Domain/Entities/Lesson.cs
-- [x] Create Domain/Entities/UserProgress.cs
+- [ ] Create Domain/Entities/UserProgress.cs
-- [x] Create Domain/Interfaces/ILevelRepository.cs
+- [ ] Create Domain/Interfaces/ILevelRepository.cs
-- [x] Create Domain/Interfaces/ILessonRepository.cs
+- [ ] Create Domain/Interfaces/ILessonRepository.cs
-- [x] Create Infrastructure/Data/Repositories/LevelRepository.cs
+- [ ] Create Infrastructure/Data/Repositories/LevelRepository.cs
-- [x] Create Infrastructure/Data/Repositories/LessonRepository.cs
+- [ ] Create Infrastructure/Data/Repositories/LessonRepository.cs
-- [x] Create Infrastructure/Data/Repositories/UserProgressRepository.cs
+- [ ] Create Infrastructure/Data/Repositories/UserProgressRepository.cs
-- [x] Create Application/DTOs/LevelDto.cs
+- [ ] Create Application/DTOs/LevelDto.cs
-- [x] Create Application/DTOs/LessonDto.cs
+- [ ] Create Application/DTOs/LessonDto.cs
 - [ ] Create Application/DTOs/UserProgressDto.cs
 - [ ] Create Application/Services/LevelService.cs
 - [ ] Create Application/Services/LessonService.cs
@@ -203,11 +201,11 @@ Each lesson contains:
 - [ ] Write integration tests for controllers
 
 ### Database
-- [x] Create migration for Levels table
+- [ ] Create migration for Levels table
-- [x] Create migration for Lessons table
+- [ ] Create migration for Lessons table
-- [x] Create migration for UserProgress table
+- [ ] Create migration for UserProgress table
-- [x] Seed A1 level with initial lessons
+- [ ] Seed A1 level with initial lessons
-- [x] Add indexes for performance
+- [ ] Add indexes for performance
 
 ### Business Logic
 - [ ] Implement LessonUnlockService